Drive circuit unit, head unit, and liquid ejecting apparatus

Abstract

A drive circuit unit is provided in a head unit together with a head and is configured to generate a drive signal for driving the head. The drive circuit unit includes a base board that includes a drive-circuit-unit-side connector coupled to a head-side connector; and a plurality of drive circuit boards on each of which a drive circuit configured to generate a drive signal is mounted, wherein the base board is disposed such that the base board extends in a direction intersecting with a nozzle surface of the head, and the plurality of drive circuit boards is disposed on the base board.

What is claimed is: 
     
         1 . A drive circuit unit provided in a head unit together with a head and configured to generate a drive signal for driving the head, the drive circuit unit comprising:
 a base board that includes a drive-circuit-unit-side connector coupled to a head-side connector; and   a plurality of drive circuit boards on each of which a drive circuit configured to generate a drive signal is mounted, wherein   the base board is disposed such that the base board extends in a direction intersecting with a nozzle surface of the head, and   the plurality of drive circuit boards is disposed on the base board and is coupled to the base board in a direction intersecting with the direction in which the base board extends.   
     
     
         2 . The drive circuit unit according to  claim 1 , wherein
 the plurality of drive circuit boards is coupled to the base board such that the plurality of drive circuit boards extends in a direction substantially perpendicular to the nozzle surface.   
     
     
         3 . The drive circuit unit according to  claim 1 , wherein
 the drive circuit board further includes a slight vibration generating circuit that generates a slight vibration signal for causing liquid vibration to an extent that no liquid is ejected from a nozzle provided in the head.   
     
     
         4 . The drive circuit unit according to  claim 1 , wherein
 the drive circuit is a class-D amplifier that includes an integrated circuit, a transistor, and a coil.   
     
     
         5 . The drive circuit unit according to  claim 4 , wherein
 the drive circuit board includes a coupling connector coupled to the base board, and   a distance between the coupling connector and the coil is shorter than a distance between the coupling connector and the integrated circuit.   
     
     
         6 . The drive circuit unit according to  claim 5 , wherein
 the coupling connector includes
 a first terminal through which a drive signal propagates to an upper electrode included in a piezoelectric element provided in the head, 
 a second terminal through which a drive signal having an amplitude different from that of the drive signal propagating through the first terminal propagates to the upper electrode, and 
 a third terminal through which a constant voltage signal propagates to a lower electrode included in the piezoelectric element, and 
   the third terminal is disposed between the first terminal and the second terminal.   
     
     
         7 . The drive circuit unit according to  claim 5 , wherein
 the drive circuit board further includes a slight vibration generating circuit that generates a slight vibration signal for causing liquid vibration to an extent that no liquid is ejected from a nozzle provided in the head,   the coupling connector includes
 a fourth terminal through which a drive signal propagates to an upper electrode included in a piezoelectric element provided in the head, 
 a fifth terminal through which a drive signal having an amplitude different from that of the drive signal propagating through the fourth terminal propagates to the upper electrode, and 
 a sixth terminal through which the slight vibration signal propagates, and 
   the sixth terminal is disposed between the fourth terminal and the fifth terminal.   
     
     
         8 . A head unit, comprising:
 a drive circuit unit; and   a head,   the head including
 an ejecting portion that, upon receiving a drive signal supplied from the drive circuit unit, ejects liquid from a nozzle provided in a nozzle surface, and 
 a collective board that includes a head-side connector, 
   the drive circuit unit including
 a base board that includes a drive-circuit-unit-side connector coupled to the head-side connector; and 
 a plurality of drive circuit boards on each of which a drive circuit configured to generate the drive signal is mounted, wherein 
   the base board is disposed such that the base board extends in a direction intersecting with the nozzle surface, and   the plurality of drive circuit boards is disposed on the base board and is coupled to the base board in a direction intersecting with the direction in which the base board extends.   
     
     
         9 . A liquid ejecting apparatus, comprising:
 a plurality of sets each including a plurality of head units and a transportation unit, the head unit including a drive circuit unit and a head,   the head including
 an ejecting portion that, upon receiving a drive signal supplied from the drive circuit unit, ejects liquid from a nozzle provided in a nozzle surface, and 
 a collective board that includes a head-side connector, 
   the drive circuit unit including
 a base board that includes a drive-circuit-unit-side connector coupled to the head-side connector; and 
 a plurality of drive circuit boards on each of which a drive circuit configured to generate the drive signal is mounted, wherein 
   the base board is disposed such that the base board extends in a direction intersecting with the nozzle surface,   the plurality of drive circuit boards is disposed on the base board, and   the plurality of head units is arranged in a first direction parallel to the nozzle surface.